what size headers

[codytr1]

i am building a 454 for my blazer. it has a stock bottom end, pocket ported 781 heads, 2.19 & 1.88 valves, 9.75 compression, comp cams extreme energy 268 cam edelbrock performer rpm intake, & 770 truck avenger carb. What size headers should I put on ? By that Imean what size primaries, any help would be appreciated

 

[4X4HIGH]

1 7/8" should be fine.

 

[codytr1]

any reason not to go 1 3/4 or 2inch

 

[blazin_blazer]

any reason not to go 1 3/4 or 2inch

1 7/8ths right between those 2 #'s or are u askin any reason not to step down or up a size?

 

[codytr1]

why not go up or down in size

 

[4X4HIGH]

why not go up or down in size

Because smaller isn't big enough and larger is too big.

 

[codytr1]

on a budget what way would you go bigger or smaller the 1 7/8 headers i found were between $300.00 and $550.00

 

[4X4HIGH]

In this case always go smaller.

 

[codytr1]

thank you very much

 

[blazin_blazer]

i just put a motor in w/headers, i had them just uncorked, and adjusted my valves out, and had to fiddle w/carb,..the darn thing wouldn't idle, had to set idle way high and still verry choppy...i was wonderin if i had grossly over-cammed it...had the exhaust put on, it tamed the cam and let me set idle back down like it should of been,..it seems that the sbc likes a little resistance on exhaust